This invention relates generally to vehicle parking brake actuators and, more particularly, to an improved operating lever for operating the parking brake actuator.
Several types of hand- and foot-operated parking brake actuators are in use. One popular foot-operated parking brake actuator uses an operating lever which mounts a sector gear that is in constant mesh with a pinion. A torsion spring has one fixed and one free end and grips the pinion hub as a one-way clutch. This allows the pinion to rotate as the operating lever is moved to a brake-apply position, but prevents reverse rotation to latch the lever in the brake-apply position.
The torsion spring free end is engaged by a brake release member to spread the spring and release the pinion hub to unlatch the pinion, which releases the lever for movement to brake-released position. One such parking brake actuator is disclosed in U.S. Pat. No. 3,236,120 to Fender in which the torsion spring is releasable by a vacuum actuator. In many current vehicles, this type of parking brake actuator has been modified to replace the vacuum actuator with an electric actuator, as shown in U.S. Pat. No. 5,029,681 to Swiatek.
Contemporary parking brake actuators utilize a stamped or cast steel operating lever. Hand-operated levers are fitted with a plastic or leather handgrip. In foot-operated parking brake actuators, the steel lever is fitted with a rubber footpad. Because of their construction, these operating levers are heavy and relatively expensive. Also, the rubber footpads wear rapidly, causing increased warranty expense for the vehicle manufacturer.
There is a need for an improved operating lever for a parking brake actuator that is lighter and cheaper than contemporary operating levers and which is constructed to reduce warranty expenses.